#!/usr/bin/env python3

class Student:
    __slots__ = ('name', 'age', 'sex')

    def show(self):
        print(self.name)


def run(self):
    print("run....")

def main():
    Student.cn = 57
    #  Student.run = run
    Student.run = lambda self: print("run....")

    s = Student()
    s.name = "hello"
    setattr(s, 'age', 32)
    s.sex = 'A'
    #  s.__dict__['sex'] = 'A'
    #  s.en = 35
    #  del s.__dict__['name']
    #  print(s.__dict__)
    #  s.show()

    s.run()

    print(s.name, s.age, s.sex)

if __name__ == "__main__":
    main()
